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Comment by aktau | Hacker News Reader

I concur, runit absolutely rocks. Haven't tried systemd yet, I wonder if the two play nice together (if they don't, it won't be runits' fault, that's for sure).

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Might try the old-school daemontools, even though the commands are a bit different, it might be less work to get something going.

From your other comments I can tell you're a seasoned daemontools user, so let me just put in a quick plug for daemontools-encore [1]. Like runit, daemontools-encore can now run services in separate process groups with setsid(1). Why is this so darn important? Well, under classic daemontools a ./run file with a pipeline in it -- or really anything that forked -- would spin off orphans every time you did `svc -t|-k`. Very bad stuff to deal with in a production environment.

[1] http://untroubled.org/daemontools-encore/

Yup, it's one of those annoying things that makes run scripts more complicated. I rewrote phusion's runit setuser helper in Go because it didn't set all the right env vars.

https://raw.githubusercontent.com/steakknife/my_init/master/...

Huh, looks pretty similar to envuidgid(8) from daemontools. [1]

Another plug for daemontools-encore (last one I promise). The setuidgid(8) program in classic daemontools doesn't set supplementary groups, and a lot of people I know just end up just using sudo in their run files. If you use daemontools-encore though, you can just use `setuidgid -s` instead.

PS. Really, daemontools-encore should imo be called daemontools 1.x, but you know how djb feels about forks of his projects...

[1] http://cr.yp.to/daemontools/envuidgid.html

Maintainers either will or won't accept that forks are the sincerest form of flattery.

The problem as per the Phusion blog article is that the runit and possibly daemontools equivalent commands don't set all env vars: HOME, USER, GID & UID, it only calls setgid() & setuid() IIRC. (envuidgid only sets UID and GID[0]) This causes breakage for lots of apps that end up inheriting root's env instead. :(

Here's the go version I wrote, so there's no need for dep on Python/Ruby/etc on the target system:

    setuser USERNAME COMMAND [args...]

    # how to build it
    go get   github.com/steakknife/my_init/setuser
    go build github.com/steakknife/my_init/setuser
    # creates setuser exe here

[0] FR issue submitted as https://github.com/bruceg/daemontools-encore/issues/18

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